The Lockheed HULC exoskeleton was covered here Previously a jet fuel generator was needed to get this level of endurance.
Protonex will evaluate fuel cell-based power solutions that can be carried by the HULC, while at the same time powering the exoskeleton and the user’s mission equipment during extended dismounted operations.
"Integrating state-of-the-art power technology on the HULC is a whole system approach to meeting the needs of dismounted Warfighters and Special Operations forces," said Rich Russell, director of Sensors, Data Links and Advanced Programs at Lockheed Martin Missiles and Fire Control. “With proper power management systems, the HULC can be used to recharge critical equipment while carrying heavy combat loads on an extended mission."
Dismounted Soldiers often carry loads greater than 130 pounds, including electronics and numerous extra batteries needed to operate gear and complete 72+-hour operations in the field. The HULC, equipped with an extended mission power supply with recharge capability, would enable dismounted Soldiers on these missions to carry fewer batteries
* Soldiers will be able to carry loads up to 200 pounds with minimal effort
* HULC uses four pounds of lithium polymer batteries will run the exoskeleton for an hour walking at 3mph, according to Lockheed. Speed marching at up to 7mph reduces this somewhat; a battery-draining "burst" at 10mph is the maximum speed
A soldier with a pack would normally go at 3 mph maximum and cover 10-12 miles in a day.
* Remote-controlled gun mounts weighing as little as 55lb are available, able to handle various kinds of normally tripod- or bipod-mounted heavy weapons
* HULC is basically a legs and body system only: there's no enhancement to the user's arms, though an over-shoulder frame can be fitted allowing a wearer to hoist heavy objects such as artilery shells with the aid of a lifting strop.
NOTE: Average humans walk 4 to 6 mph, but special operations soldiers are often expected to carry up to 150 pounds of supplies in their backpacks. 25mph speed with bionic boots (springing the step) would be covering almost a marathon distance in one hour.